Ferrous welding electrode for manual arc welding



United States Patent No Drawing. Filed Aug. 10, 1965, Ser. No. 478,731

j 8 Claims; (Cl. 219-446) This inventionrelates to a ferrous welding electrode for manual arc welding. More particularly, it relates to a ferrous welding electrode for manual arc welding for accomplishment of a commercially acceptable welding operation While transferring titanium from the electrode across an electric arc to form a weld deposit containing titanium carbide precipitated in situ for increased wear resistance.

In copending United States patent application Ser. No. 288,075,- filed June, 17, 1963, now Patent No. 3,231,709, there are disclosed a welding method and electrode for producing a weld deposit containing titanium carbide particles. crystallized in situ in the solidifying weld metal. The application discloses that the presence of from about 1% to about.20% of such crystallized titanium carbide byweight-of the weld deposit provides greatly increased wear resisting properties in the deposit which is a significant advantage in hard facing overlays subjected to severe high stress abrasion. The application establishes that ti- .tanium from various sources can be efiiciently transferred across an electric arc in the presence of high carbon; as a result, titanium carbide crystals can be precipitated in situ in the solidifying deposit.

-.T he invention disclosed in said application is workable and can produce the desired end result, i.e., a weld decreased wear resistance. However, I found that whenever posit containing particles of titanium carbide for increased wear resistance. However, I found that whenever more than about 1.6% titanium by weight of the electrode metal was added by incorporating it into the electrode coating either as the metal itself or as one of'its compounds the transfer of such titanium across the are usually adversely afiectbd operation of the electrode. Electrode metal is defined as the sum of the carbon and, the metallic components either present in the electrode or recoverable from compounds present in it. Operation of early electrodes formulated to provide the desired deposit was so poor as to be considered only marginally salable. This poor welding operation had the following listed characteristics:

(a) The molten slag interfered with the are by floating across the pool of molten metal and going under the arc.

(b) The burning olf of the electrode produced voluminous clouds of smokewhich interfered with vision and irritated the welders eyes. (c) Spatter was very high, and large globs of metal exploded from the arc and left the area of the molten weld metal pool.

(d) The resulting deposit often contained porosity because of (a) and (c).

(c) It was diflicult to control the molten weld metal.

Thus, prior to my invention a situation existed wherein a very useful weld deposit was possible but no coated manual welding electrode had been made which Would produce such a deposit in the performance of commercially acceptable welding operation.

I have found that titanium in amounts up to about 1.6%; by weight of the electrode metal can be transferred from the coating of a coated manual welding electrode across an electric arc with no adverse elfect on welding operation, but to maintain such commercially acceptable op- 3,398,257 Patented Aug. 20, 1968 ice eration at higher titanium levels all titanium in excess of about 1.6% by weight of the electrode metal, and preferably all titanium in excess of about 1.4% by weight of the electrode metal, should be incorporated in the fill of a composite electrode comprising a tubular sheath With fill inside the sheath and a coating on the outside of the sheath, where such titanium is provided in the form of titanium metal, alloys of titanium with other metal or titanium carbide. Moreover, I have found that the welding operation under such conditions can be further improved. if the total carbon in the electrode is maintained in the range specified hereinbelow. For best results the electrodes may be coated with a conventional consumable type coating (i.e., carbon, alloy, binder and only minor amounts of other slag forming ingredients).

I provide a ferrous welding electrode for manual arc welding comprising a tubular sheath with fill inside the sheath and a coating on the outside of the sheath, the sheath being of ferrous metal, the electrode containing titanium, the coating containing no more than about 1.6% titanium and preferably no more than about 1.4% titanium, the fill con-taining up to about 22% titanium, the titanium of the fill being contained in at least one of the materials of the group consisting of titanium metal, alloys of titanium with other metal and titanium carbide, the total amount of titanium in the electrode being equal to from about 1% to about 22%, the electrode also containing carbon in an amount equal to not less than about percent titanium+l.0%) and not more than about (M: X percent titanium+9.0%), all percentages being by weight of the electrode metal. The weight of the fill is equal to from about 20% to about 50%, preferably from about 25% to about 30%, of the total weight of the sheath and fill together. The weight of the coating is equal to from about 10% to about 30%, preferably from about 18% to about 22%, of the total weight of the sheath, fill and coating together. This provides a rather thin consumable coating which is advantageous in that it is not as refractory as a thicker coating would be and thus is consumed more easily.

The limits of carbon defined above, when applied to the titanium limits specified, result in an overall carbon range which is somewhat narrower than that specified in the above mentioned application; however, this restriction is necessary to the accomplishment of a commercially acceptable welding operation.

The term commercially acceptable welding operation means a welding operation in which (a) there is minimum interference due to slag under the arc, (b) the smoke level is low enough to afford good visibility and not to irritate the welder, (c) the spatter level is low so that very little metal is lost to the air or other sections of the base plate around the deposit, ((1) there is minimum porosity in the deposit and (e) the metal is easily controlled by the welder.

It is my belief that the concentration of all titanium above about 1.6% by weight of the electrode metal in the fill inside the tubular sheath in one of the forms listed is beneficial to operation because in this location the titanium obtains maximum protection from reaction with the oxygen and nitrogen of the air. I have also observed that incorporating titanium in the fill inside the tubular sheath makes the molten weld metal pool more fluid and easy to control, presumably because of the increased protection afforded the titanium by the metallic sheath and electrode coating.

Other details, objects and advantages of the invention will become apparent as the following description of certain present preferred embodiments thereof proceeds.

The accompanying table lists data on eight ferrous welding electrodes for manual arc welding which I have 3 r l .5 tested. Electrodes numbered 7 and 8 are specific embodiequal to'from'about 25% to about 30% of the total weight ments of my invention. All electrodes were of a nominal e ofthe sheath and fill together and the coating contains no 7 diameter. Except for the variation in titanium and more than about 1.4% titanium by weight of the eleccarbon contents listed the electrode coatings were all trode metal. similar, being of the conventional consumable type de- 5 4. A ferrous welding electrode for manual arc welding scribed hereinabove. Under the heading Welding Operaas claimed in claim 1 in whichthe weight of the fill is tion, Poor means non-salable or marginally salable equal to'from about to 'about 50%61? the total and Good means commercially acceptable as defined weight of the sheath and fill together andthe weight of previously. The carbon contents of all electrodes are with; the coating is equal to from about 10% toaibout 3 0% of in the above defined range. 4 the total weight 'of the sheath, fill and c oating together;.

Electrode Type Coating 4 Total :rbmi' Welding NO, percent Ti 'PercentC Operation Description Percent Ti Percent C Percent 3 Percent Ti Percent G2 in Elect. in Elect.

.. Solid wire 0 .2 32.3 4.6 4.6 4.6 48 Poor.

Tubular, 23.5% Ful 4.2 4.0 34.2 4.8 5.1 9. 0 9.1 "Do. 4 Solid wire 0 .2 30.0 3.5 5.1 3.5 5.3 .115. 5 Tubular, 28.5% F111 4.1 3.9 34.0 4.0 5.3 8.1 9.7 Do. 6. Solidwire 0 .2 30.6 4.9 6.8 4.9 7.0 5B0. 7 Tubular, 27.5% Fill 6.3 4.1 20.0 0 4.9 0.3 9.0 Good. 8 Tubular, 25.3% Fill 1 Percent of total weight of sheath and fill together. v

9 Percent by weight of electrode metal.

3 Percent of total weight of sheath, fill and coating together.

It can be seen from the table that commercially ac- 5. A ferrous welding electrode for manual are weldceptable welding operation was not achieved until both ing as claimed in claim 1 in which the weight of'the' fill the titanium and the carbon conformed to the requireis equal to from about 20% to about 50% of the total ments of my invention as given hereinabove. weight of the sheath and fill together and the weight of While I have described certain present preferred emthe coating is equal to from about 18% to about 22% of bodiments of my invention it is to be distinctly underthe total weight of the sheath, fill and coating'togeth'er.

stood that the invention is not limited thereto but may 6. A ferrous welding electrode for manual arc welding be otherwise variously embodied within the scope of the as claimed in claim 4 in which the coating contains no following claims. more than about 1.4% titanium by Weight of the electrode 1 claim: metal.

1. A ferrous welding electrode for manual arc welding 7. A ferrous welding electrode for manual'arc welding comprising a tubular sheath with fill inside the sheath as claimed in claim 5 in which'the coating contains no and a coating on the outside of the sheath, the sheath bemore than about 1.4% titanium by weight of the elecing of ferrous metal, the electrode containing titanium, trode metal. the coating containing no more than about 1.6% titanium, 8. A ferrous welding electrode for manual arc welding the fill containing up to about 22% titanium, the titanium as claimed in claim 1 in which the Weight of the fill is of the fill being contained in at least one of the materials 40 equal to from about 25% to about 30% of the total of the group consisting of titanium metal, alloys of titaweight of the sheath and fill together, andthe'weight of nium with other metal and titanium carbide, the total the coating is equal to from about 18% to about 22% of amount of titanium in the electrode being equal to from the total weight of the sheath, fill and coating together about 1% to about the electrode also Containing and in which the coating contains no more than about carbon in an amount equal to not less than about 1.4% titanium by weight of the electrode metal.

( A4 percent titanium+1.0 percent) and not more than I about A percent titanium-|-9.0 percent), all percent- References Cited ages being by weight of the electrode metal. UNITED STATES PATENTS 2. A ferrous welding electrode for manual are welding as claimed in claim 1 in which the weight of the fill 3,036,205 5/1962 i et 2.1,9 is equal to from about 20% to about 50% of the total 3. 7/ 1967 Quaas 9-1 weight of the sheath and fill together and the coating con- 3,345,495 7 10/1967 Quaas et '1 tains no more than about 1.4% titanium by weight of v the electrode metal RICHARD M. WOOD, Plzmar y Exqmzne 3. A ferrous welding electrode for manual arc welding B. A. STEIN, Assistant Examiner. as claimed in claim 1 in which the weight of the fill is I UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Ratent No. 3,398,257 August 20, 1968 Albert E. Wiehe It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 35, cancel "creased wear resistance.

However, I found that whenever".

Signed and sealed this 13th day of January 1970.

(SEAL) Attest:

Edward M. Fletcher, J1. J

Commissioner of Patents Attesting Officer 

1. A FERROUS WELDING ELECTRODE FOR MANUAL ARC WELDING COMPRISING A TUBULAR SHEATH WITH FILL INSIDE THE SHEATH AND A COATING ON THE OUTSIDE OF THE SHEATH, THE SHEATH BEING OF FERROUS METAL, THE ELECTRODE CONTAINING TITANIUM, THE COATING CONTAINING NO MORE THAN ABOUT 1.6% TITANIUM, THE FILL CONTAINING UP TO ABOUT 22% TITANIUM, THE TITANIUM OF THE FILL BEING CONTAINED IN AT LEAST ONE OF THE MATERIALS OF THE GROUP CONSISTING OF TITANIUM METAL, ALLOYS OF TITANIUM WITH OTHER METAL AND TITANIUM CARBIDE, THE TOTAL AMOUNT OF TITANIUM IN THE ELECTRODE BEING EQUAL TO FROM ABOUT 1% TO ABOUT 22%, THE ELECTRODE ALSO CONTAINING CARBON IN AN AMOUNT EQUAL TO NOT LESS THAN ABOUT (1/4XPERCENT TITANIUM+1.0 PERCENT) AND NOT MORE THAN ABOUT (1/4XPERCENT TITANIUM+9.0 PERCENT), ALL PERCENTAGES BEING BE WEIGHT OF THE ELECTRODE METAL. 